The invention relates to a road with at least one traffic lane for motorized vehicular traffic, to which road are added sound attenuating means which limit, at least for determined frequency ranges, the lateral emission of sound caused by traffic travelling over the road.
Such a road is known. A known road comprises sound attenuating means in the form of a noise-reducing screen or a noise barrier. Behind a noise-reducing screen there is a “shadow side”, whereby traffic noise, in particular sound from rolling tyres, is attenuated. Noise-reducing screens are reasonably effective, particularly in the case of houses in the vicinity of such a road, in at least limiting the worst noise nuisance.
The sound frequencies are concentrated in a spectral range around about 1 kHz, in particular the frequency band of about 700 to 1,300 Hz, as shown in inter alia “Euronoise Naples 2003, paper ID 498 ‘The Multi-Coincidence Peak around 1000 Hz in Tyre/Road noise spectra’, Ulf Sandberg”.
Noise-reducing screens or noise barriers are expensive provisions. They further have an adverse effect on the landscape and often deprive residents of an unobstructed view. They moreover have the drawback that their effectiveness is limited in the case of specific wind directions.
It is further known that particular types of road surface, for instance the very open asphalt concrete, or ZOAB, can bring about a substantial reduction in the sound caused by tyres. A sound reduction from several dB up to about 7 dB can hereby be realized. It is nevertheless desirable, particularly in view of the greatly increased traffic intensity, to realize a further additional sound reduction.